Roll the butter in the paper to shape into a round log and twist the ends of the paper to seal.
Place the butter roll in the freezer for at least half an hour to firm.
Remove butter from the freezer and slice into rounds with a hot, sharp knife.
Notes
Remove the butter from the fridge at least an hour before you start so that it can soften at room temperature. Otherwise you can soften it slightly in the microwave for a short time on low to medium heat.